\documentclass{article}
\usepackage{amssymb,amsmath,amscd,concmath}
\pagestyle{empty}
\begin{document}
\begin{equation*}\frac{d}{d t} \int_{\Omega}  L d\Omega = -\int_{\Omega} \nabla\cdot ( L\mathbf{v} ) d\Omega + \int_{\Omega} Q d\Omega \end{equation*}
\end{document}
